Biphenyl derivatives are compounds widely used in fields of organic and polymer chemistry, and, useful compounds in fields that cover wide industrial applications such as fine chemicals, medical and agrochemical raw materials, resins and plastics raw materials, electronic information materials, and optical materials.
Methods for producing biphenyl derivatives are known wherein aromatic halogen compounds are used as a starting substrate. Japanese Patent Application Kokai Publication No. Sho 63-295520 (Examples 1, 3, 4) proposes that a Grignard reagent of an aromatic chloride be reacted with an aromatic bromide in the presence of a nickel catalyst. On the other hand, ORGANIC LETTERS, Vol. 7, No. 3 (2005), 491 493, and ORGANIC LETTERS, Vol. 7, No. (2005), 1943-1946 propose a production method that includes: reacting an aromatic iodide or an aromatic bromide with magnesium to convert them into a Grignard reagent; and then mutually coupling the Grignard reagent under the coexistence of an oxidant by use of the iron chloride (III) catalyst.
However, the method described in Japanese Patent Application Kokai Publication No. Sho 63-295520 (Examples 1, 2, 3, 4) cannot be industrially applied to the case where an aromatic chloride is used as a substrate to be reacted with a Grignard reagent, because the yield of a biphenyl derivative, is low. Moreover, the production methods described in ORGANIC LETTERS, Vol. 7, No. 3 (2005), 491-493, and ORGANIC LETTERS, Vol. 7, No. 10 (2005), 1943-1946 make the produced biphenyl derivative expensive because the methods employ as a stating substrate an aromatic iodide or an aromatic bromide, both of which are highly reactive but expensive. In addition, the oxidants described in ORGANIC LETTERS, Vol. 7, No. 3 (2005), 491-493, and ORGANIC LETTERS, Vol. 7, No. 10 (2005), 1943-1946 are 1,2-dibromoethane and 1,2-dichloroethane, and these belong to Group 2A (material that is probably carcinogenic to humans) and Group 2B (material that possibly carcinogenic to humans), respectively, according to carcinogenic evaluations by International Agency for Research on Cancer (IARC). In particular, 1,2-dichloroethane is specified as a banned substance in Europe.
Industrial use of these materials may cause problems and alternative materials with lower toxicity have been desired.
It could therefore be helpful to provide a method for producing a biphenyl derivative that offers an industrially high yield and is excellent in productivity by use of inexpensive and low toxic raw materials.